ai {
  --bg-paper: #F7F3E8;
  --bg-light: #FFFEF9;
  --ink-dark: #2C4A3E;
  --ink-gray: #6B8E7E;
  --accent-red: #C8503F;
  --accent-gold: #D4AF37;
  --border-light: #D4E4DC;
  --shadow-soft: rgba(44, 74, 62, 0.08);
  display: block;
  max-width: 680px;
  margin: 0 auto;
  padding: 0;
  background: linear-gradient(180deg, var(--bg-paper) 0%, var(--bg-light) 100%);
  font-family: 'LXGW WenKai', 'Noto Serif SC', serif;
  font-size: 15px;
  line-height: 1.8;
  color: #3a3a3a;
}
ai bar {
  display: block;
  position: sticky;
  top: 0;
  z-index: 100;
  padding: 10px 16px;
  background: rgba(247, 243, 232, 0.85);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-light);
  font-size: 13px;
  color: var(--ink-gray);
  text-align: center;
  letter-spacing: 0.3px;
}
ai bar::before {
  content: '';
  position: absolute;
  top: -40px;
  left: 0;
  right: 0;
  height: 40px;
  background: linear-gradient(90deg, transparent, var(--accent-red) 50%, transparent);
  opacity: 0.15;
  filter: blur(20px);
}
ai article {
  display: block;
  padding: 20px 18px 24px;
  text-align: justify;
  font-size: 15px;
  line-height: 2;
  color: #2a2a2a;
}
ai article::first-letter {
  float: left;
  font-size: 3em;
  line-height: 0.9;
  margin: 0.08em 0.12em 0 0;
  font-weight: 700;
  color: var(--ink-dark);
  text-shadow: 
    -1px -1px 0 var(--accent-red),
    1px -1px 0 var(--accent-red),
    -1px 1px 0 var(--accent-red),
    1px 1px 0 var(--accent-red);
}
ai details {
  display: block;
  margin: 12px 16px;
  border: 1px solid var(--border-light);
  border-radius: 6px;
  overflow: hidden;
  background: var(--bg-light);
  box-shadow: 0 2px 6px var(--shadow-soft);
}
ai details summary {
  display: block;
  padding: 11px 14px;
  background: linear-gradient(135deg, var(--ink-dark) 0%, #3d5f4f 100%);
  color: var(--accent-gold);
  font-weight: 600;
  font-size: 14px;
  cursor: pointer;
  user-select: none;
  transition: all 0.25s ease;
  position: relative;
}
ai details summary::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(212, 175, 55, 0.5) 50%, transparent);
}
ai details summary:hover {
  transform: translateY(-1px);
  box-shadow: 0 3px 10px rgba(44, 74, 62, 0.2);
  background: linear-gradient(135deg, #3d5f4f 0%, var(--ink-dark) 100%);
}
ai details p {
  margin: 0;
  padding: 10px 14px;
  border-bottom: 1px dashed var(--border-light);
  font-size: 14px;
  line-height: 1.7;
}
ai details p:last-child {
  border-bottom: none;
}
ai f {
  display: inline;
  font-weight: 700;
  color: var(--ink-dark);
  font-size: 13px;
  margin-right: 6px;
}
ai d {
  display: inline;
  color: var(--ink-gray);
  font-weight: 300;
}
ai em {
  display: block;
  margin-top: 4px;
  padding: 8px 12px;
  background: rgba(212, 228, 220, 0.4);
  border-left: 3px solid var(--accent-red);
  font-style: normal;
  color: #4a4a4a;
  font-size: 13px;
  line-height: 1.6;
}
ai details:nth-of-type(4) p {
  padding: 9px 14px;
  cursor: pointer;
  transition: all 0.2s ease;
  border-radius: 4px;
  margin: 4px 8px;
  border: 1px solid transparent;
}
ai details:nth-of-type(4) p:hover {
  background: var(--accent-red);
  color: #fff;
  transform: scale(1.02);
  border-color: var(--accent-red);
  box-shadow: 0 2px 8px rgba(200, 80, 63, 0.3);
}
ai details[open] summary::after {
  content: '▴';
  float: right;
  color: var(--accent-gold);
  font-size: 12px;
}
ai details:not([open]) summary::after {
  content: '▾';
  float: right;
  color: var(--accent-gold);
  font-size: 12px;
}
ai p strong {
  color: var(--ink-dark);
  font-weight: 600;
}